“Invasive species” — it doesn’t sound very threatening, does it? But these invaders, large and small, have devastating effects on U.S. wildlife. Invasive species are one of the leading threats to native wildlife. Approximately 42% of Threatened or Endangered species are at risk primarily due to invasive species.

Human health and economies are also at risk from invasive species. The impacts of invasive species on our natural ecosystems and economy cost billions of dollars each year. Many of our commercial, agricultural, and recreational activities depend on healthy native ecosystems.

What makes a species invasive?

An invasive species does not have to come from another country. For example, lake trout are native to the Great Lakes, but are considered to be an invasive species in Yellowstone Lake in Wyoming because they compete with native cutthroat trout for habitat. An invasive species can be any kind of living organism—an amphibian (like the cane toad pictured left), plant, insect, fish, fungus, bacteria, or even an organism’s seeds or eggs—that is not native to an ecosystem and which causes harm. They can harm the environment, the economy or even, human health. Species that grow and reproduce quickly, and spread aggressively, with potential to cause harm, are given the label of “invasive”

What you can do to help curb the spread of invasive species

Plant native plants and remove any invasive plants in your garden. There are many good native plant alternatives to common exotic ornamental plants.

Learn to identify invasive species in your area. Report any sightings to your county extension agent or local land manager. Learn more about invasive species in your state.

Regularly clean your boots, gear, boat, tires and any other equipment you use outdoors to remove insects and plant parts that may spread invasive species to new places.

When camping, buy firewood near your campsite (within 30 miles) instead of bringing your own from home, and leave any extra for the next campers. Invertebrates and plants can easily hitch a ride on firewood you haul to or from a campsite — you could inadvertently introduce an invasive to a new area.